2.5 A peak gate drive with 5000 Vrms isolation
The onsemi FOD3180SD is a 1-channel optoisolated gate driver in an 8-SMD Gull Wing package, designed to drive power MOSFETs and IGBTs across a galvanic isolation barrier. Its 2.5 A peak output current (2 A source/sink rated) directly charges the gate capacitance of medium-power switching devices, with a 200 ns max propagation delay keeping the switching timing tight enough for 20-100 kHz SMPS and motor drive applications.
15 kV/µs CMTI — why it matters for motor drives
Common-mode transient immunity is the optocoupler's ability to reject fast voltage swings across the isolation barrier — exactly what happens when a motor drive's IGBT switches a 600 V DC bus in tens of nanoseconds. The FOD3180SD's minimum 15 kV/µs CMTI means the output stays in the correct state even when the ground on the power side jumps several hundred volts in a few nanoseconds; below that threshold, the output can glitch and mis-fire the gate. For a 1200 V IGBT switching at 8-16 kHz, this spec is the difference between a clean commutation and a shoot-through event.
75 ns rise, 55 ns fall — gate charge delivery rate
Rise and fall times of 75 ns and 55 ns typical determine how fast the gate driver can push charge into the power device's input capacitance. For a typical IGBT with 15 nC of gate charge at 15 V, the FOD3180SD's 2 A peak output charges the gate in roughly 7.5 ns — the rise time then becomes the dominant term in the total switching loss. The 65 ns max pulse width distortion means the on and off delays are matched within that window, so the dead-time margin in a half-bridge leg doesn't need extra guard banding.
10 V to 20 V output supply — fits standard gate drive rails
The output side operates from 10 V to 20 V, covering the typical gate drive voltages for IGBTs (15 V) and power MOSFETs (10-12 V). The 25 mA max forward current keeps the LED power dissipation manageable in the 8-SMD package.